Semiconductor module device having a desired electrical circuit constituted by combination of seminconductor devices formed on circuit boards

Abstract

A semiconductor module device according to the present invention includes a disk-shaped DBC circuit board which are divided into, e.g., six sectorial DBC circuit boards. A plurality of semiconductor pellets are arranged in a staggered fashion on each of the sectorial DBC circuit boards. Externally leading electrodes are provided at the respective innermosts of the sectorial DBC circuit boards, and externally leading power terminals, which are connected to the externally leading electrodes, are extracted from the central part of the DBC circuit board. With this constitution, the distances between the externally leading power terminals and the sectorial DBC circuit boards can be minimized, and the distances between the externally leading power terminals and the semiconductor pellets on the sectorial DBC circuit boards can be uniformed, with the result that the efficiency and reliability of the module device can be improved. Since the DBC circuit board is shaped like a disk, it can be protected from breakage due to the stress concentrated when the device is mounted.

What is claimed is: 
     
       1. A semiconductor module device comprising: a substantially rectangular heat radiation plate;   a disk-shaped circuit board on said heat radiation plate with an insulator interposed therebetween and divided into a plurality of equal-sized sectorial circuit boards;   a plurality of semiconductor devices arranged in a staggered fashion on each of said sectorial circuit boards to constitute device sections, and constituting a desired electrical circuit together with said sectorial circuit boards;   externally leading electrodes provided at respective innermost locations of said sectorial circuit boards;   externally leading terminals electrically connected to said externally leading electrodes and located at central positions of said disk-shaped circuit board in corresponding relations to said innermost locations of said externally leading electrodes; and   a plurality of mounting holes in said heat radiation plate outside said disk-shaped circuit board.   
     
     
       2. The semiconductor module device according to claim 1, wherein said disk-shaped circuit board is a DBC circuit board constituted by bonding a copper plate onto said insulator. 
     
     
       3. The semiconductor module device according to claim 1, wherein said externally leading terminals are in a central part of a resin cover covering an upper surface of said disk-shaped circuit board, and said externally leading terminals and said cover are integral with each other as one component.